indirect.xs

   1 /* This file is part of the indirect Perl module.
   2  * See http://search.cpan.org/dist/indirect/ */
   3
   4 #define PERL_NO_GET_CONTEXT
   5 #include "EXTERN.h"
   6 #include "perl.h"
   7 #include "XSUB.h"
   8
   9 #ifndef SvPV_const
  10 # define SvPV_const SvPV
  11 #endif
  12
  13 #ifndef SvPV_nolen_const
  14 # define SvPV_nolen_const SvPV_nolen
  15 #endif
  16
  17 #ifndef SvPVX_const
  18 # define SvPVX_const SvPVX
  19 #endif
  20
  21 #ifndef sv_catpvn_nomg
  22 # define sv_catpvn_nomg sv_catpvn
  23 #endif
  24
  25 /* ... Hints ............................................................... */
  26
  27 STATIC U32 indirect_hash = 0;
  28
  29 STATIC IV indirect_hint(pTHX) {
  30 #define indirect_hint() indirect_hint(aTHX)
  31  SV *id = Perl_refcounted_he_fetch(aTHX_ PL_curcop->cop_hints_hash,
  32                                          NULL,
  33                                          "indirect", 8,
  34                                          0,
  35                                          indirect_hash);
  36  return (id && SvOK(id) && SvIOK(id)) ? SvIV(id) : 0;
  37 }
  38
  39 /* ... op -> source position ............................................... */
  40
  41 STATIC HV *indirect_map = NULL;
  42 STATIC const char *indirect_linestr = NULL;
  43
  44 #define OP2STR(O) (sprintf(buf, "%u", PTR2UV(o)))
  45
  46 STATIC void indirect_map_store(pTHX_ const OP *o, const char *src, SV *sv) {
  47 #define indirect_map_store(O, S, N) indirect_map_store(aTHX_ (O), (S), (N))
  48  char buf[32];
  49  const char *pl_linestr;
  50  SV *val;
  51
  52  /* When lex_inwhat is set, we're in a quotelike environment (qq, qr, but not q)
  53   * In this case the linestr has temporarly changed, but the old buffer should
  54   * still be alive somewhere. */
  55
  56  if (!PL_parser->lex_inwhat) {
  57   pl_linestr = SvPVX_const(PL_parser->linestr);
  58   if (indirect_linestr != pl_linestr) {
  59    hv_clear(indirect_map);
  60    indirect_linestr = pl_linestr;
  61   }
  62  }
  63
  64  val = newSVsv(sv);
  65  SvUPGRADE(val, SVt_PVIV);
  66  SvUVX(val) = PTR2UV(src);
  67  SvIOK_on(val);
  68  SvIsUV_on(val);
  69  if (!hv_store(indirect_map, buf, OP2STR(o), val, 0))
  70   SvREFCNT_dec(val);
  71 }
  72
  73 STATIC const char *indirect_map_fetch(pTHX_ const OP *o, SV ** const name) {
  74 #define indirect_map_fetch(O, S) indirect_map_fetch(aTHX_ (O), (S))
  75  char buf[32];
  76  SV **val;
  77
  78  if (indirect_linestr != SvPVX_const(PL_parser->linestr))
  79   return NULL;
  80
  81  val = hv_fetch(indirect_map, buf, OP2STR(o), 0);
  82  if (!val) {
  83   *name = NULL;
  84   return NULL;
  85  }
  86
  87  *name = *val;
  88  return INT2PTR(const char *, SvUVX(*val));
  89 }
  90
  91 STATIC void indirect_map_delete(pTHX_ const OP *o) {
  92 #define indirect_map_delete(O) indirect_map_delete(aTHX_ (O))
  93  char buf[32];
  94
  95  hv_delete(indirect_map, buf, OP2STR(o), G_DISCARD);
  96 }
  97
  98 STATIC void indirect_map_clean(pTHX_ const OP *o) {
  99 #define indirect_map_clean(O) indirect_map_clean(aTHX_ (O))
 100  if (o->op_flags & OPf_KIDS) {
 101   const OP *kid = cUNOPo->op_first;
 102   for (; kid; kid = kid->op_sibling) {
 103    indirect_map_delete(kid);
 104    indirect_map_clean(kid);
 105   }
 106  } else {
 107   indirect_map_delete(o);
 108  }
 109 }
 110
 111 STATIC const char *indirect_find(pTHX_ SV *sv, const char *s) {
 112 #define indirect_find(N, S) indirect_find(aTHX_ (N), (S))
 113  STRLEN len;
 114  const char *p = NULL, *r = SvPV_const(sv, len);
 115
 116  p = strstr(s, r);
 117  while (p) {
 118   p += len;
 119   if (!isALNUM(*p))
 120    break;
 121   p = strstr(p + 1, r);
 122  }
 123
 124  return p;
 125 }
 126
 127 /* ... ck_const ............................................................ */
 128
 129 STATIC OP *(*indirect_old_ck_const)(pTHX_ OP *) = 0;
 130
 131 STATIC OP *indirect_ck_const(pTHX_ OP *o) {
 132  o = CALL_FPTR(indirect_old_ck_const)(aTHX_ o);
 133
 134  if (indirect_hint()) {
 135   SV *sv = cSVOPo_sv;
 136   if (SvPOK(sv) && (SvTYPE(sv) >= SVt_PV))
 137    indirect_map_store(o, indirect_find(sv, PL_parser->oldbufptr), sv);
 138  }
 139
 140  return o;
 141 }
 142
 143 /* ... ck_rv2sv ............................................................ */
 144
 145 STATIC OP *(*indirect_old_ck_rv2sv)(pTHX_ OP *) = 0;
 146
 147 STATIC OP *indirect_ck_rv2sv(pTHX_ OP *o) {
 148  if (indirect_hint()) {
 149   OP *op = cUNOPo->op_first;
 150   const char *name = NULL;
 151   STRLEN len;
 152   switch (op->op_type) {
 153    case OP_GV:
 154    case OP_GVSV: {
 155     GV *gv = cGVOPx_gv(op);
 156     name = GvNAME(gv);
 157     len  = GvNAMELEN(gv);
 158     break;
 159    }
 160    default: {
 161     SV *sv = cSVOPx_sv(op);
 162     if (SvPOK(sv) && (SvTYPE(sv) >= SVt_PV))
 163      name = SvPV_const(sv, len);
 164     break;
 165    }
 166   }
 167   if (name) {
 168    SV *sv = sv_2mortal(newSVpvn("$", 1));
 169    sv_catpvn_nomg(sv, name, len);
 170    const char *s;
 171    s = indirect_find(sv, PL_parser->oldbufptr);
 172    if (!s) { /* If it failed, retry without the current stash */
 173     const char *stash = HvNAME_get(PL_curstash);
 174     STRLEN stashlen = HvNAMELEN_get(PL_curstash);
 175     if ((len < stashlen + 2) || name != strstr(name, stash)) {
 176      /* Failed again ? Try to remove main */
 177      stash = "main";
 178      stashlen = 4;
 179      if ((len < stashlen + 2) || name != strstr(name, stash))
 180       goto done;
 181     }
 182     sv_setpvn(sv, "$", 1);
 183     if (name[stashlen] != ':' || name[stashlen+1] != ':')
 184      goto done;
 185     stashlen += 2;
 186     sv_catpvn_nomg(sv, name + stashlen, len - stashlen);
 187     s = indirect_find(sv, PL_parser->oldbufptr);
 188     if (!s)
 189      goto done;
 190    }
 191    o = CALL_FPTR(indirect_old_ck_rv2sv)(aTHX_ o);
 192    indirect_map_store(o, s, sv);
 193    return o;
 194   }
 195  }
 196
 197 done:
 198  return CALL_FPTR(indirect_old_ck_rv2sv)(aTHX_ o);
 199 }
 200
 201 /* ... ck_padany ........................................................... */
 202
 203 STATIC OP *(*indirect_old_ck_padany)(pTHX_ OP *) = 0;
 204
 205 STATIC OP *indirect_ck_padany(pTHX_ OP *o) {
 206  o = CALL_FPTR(indirect_old_ck_padany)(aTHX_ o);
 207
 208  if (indirect_hint()) {
 209   SV *sv;
 210   const char *s = PL_parser->oldbufptr, *t = PL_parser->bufptr - 1;
 211
 212   while (s < t && isSPACE(*s)) ++s;
 213   while (t > s && isSPACE(*t)) --t;
 214   sv = sv_2mortal(newSVpvn(s, t - s + 1));
 215
 216   indirect_map_store(o, s, sv);
 217  }
 218
 219  return o;
 220 }
 221
 222 /* ... ck_method ........................................................... */
 223
 224 STATIC OP *(*indirect_old_ck_method)(pTHX_ OP *) = 0;
 225
 226 STATIC OP *indirect_ck_method(pTHX_ OP *o) {
 227  if (indirect_hint()) {
 228   OP *op = cUNOPo->op_first;
 229   SV *sv;
 230   const char *s = indirect_map_fetch(op, &sv);
 231   if (!s) {
 232    sv = cSVOPx_sv(op);
 233    if (!SvPOK(sv) || (SvTYPE(sv) < SVt_PV))
 234     goto done;
 235    sv = sv_mortalcopy(sv);
 236    s  = indirect_find(sv, PL_parser->oldbufptr);
 237   }
 238   o = CALL_FPTR(indirect_old_ck_method)(aTHX_ o);
 239   /* o may now be a method_named */
 240   indirect_map_store(o, s, sv);
 241   return o;
 242  }
 243
 244 done:
 245  return CALL_FPTR(indirect_old_ck_method)(aTHX_ o);
 246 }
 247
 248 /* ... ck_entersub ......................................................... */
 249
 250 STATIC const char indirect_msg[] = "Indirect call of method \"%s\" on object \"%s\"";
 251
 252 STATIC OP *(*indirect_old_ck_entersub)(pTHX_ OP *) = 0;
 253
 254 STATIC OP *indirect_ck_entersub(pTHX_ OP *o) {
 255  LISTOP *op;
 256  OP *om, *oo;
 257  IV hint = indirect_hint();
 258
 259  o = CALL_FPTR(indirect_old_ck_entersub)(aTHX_ o);
 260
 261  if (hint) {
 262   const char *pm, *po;
 263   SV *svm, *svo;
 264   oo = o;
 265   do {
 266    op = (LISTOP *) oo;
 267    if (!op->op_flags & OPf_KIDS)
 268     goto done;
 269    oo = op->op_first;
 270   } while (oo->op_type != OP_PUSHMARK);
 271   oo = oo->op_sibling;
 272   om = op->op_last;
 273   if (om->op_type == OP_METHOD)
 274    om = cUNOPx(om)->op_first;
 275   else if (om->op_type != OP_METHOD_NAMED)
 276    goto done;
 277   pm = indirect_map_fetch(om, &svm);
 278   po = indirect_map_fetch(oo, &svo);
 279   if (pm && po && pm < po) {
 280    const char *psvm = SvPV_nolen_const(svm), *psvo = SvPV_nolen_const(svo);
 281    if (hint == 2)
 282     croak(indirect_msg, psvm, psvo);
 283    else
 284     warn(indirect_msg, psvm, psvo);
 285   }
 286 done:
 287   indirect_map_clean(o);
 288  }
 289
 290  return o;
 291 }
 292
 293 STATIC U32 indirect_initialized = 0;
 294
 295 /* --- XS ------------------------------------------------------------------ */
 296
 297 MODULE = indirect      PACKAGE = indirect
 298
 299 PROTOTYPES: DISABLE
 300
 301 BOOT:
 302 {
 303  if (!indirect_initialized++) {
 304   PERL_HASH(indirect_hash, "indirect", 8);
 305   indirect_map = newHV();
 306   indirect_old_ck_const    = PL_check[OP_CONST];
 307   PL_check[OP_CONST]       = MEMBER_TO_FPTR(indirect_ck_const);
 308   indirect_old_ck_rv2sv    = PL_check[OP_RV2SV];
 309   PL_check[OP_RV2SV]       = MEMBER_TO_FPTR(indirect_ck_rv2sv);
 310   indirect_old_ck_padany   = PL_check[OP_PADANY];
 311   PL_check[OP_PADANY]      = MEMBER_TO_FPTR(indirect_ck_padany);
 312   indirect_old_ck_method   = PL_check[OP_METHOD];
 313   PL_check[OP_METHOD]      = MEMBER_TO_FPTR(indirect_ck_method);
 314   indirect_old_ck_entersub = PL_check[OP_ENTERSUB];
 315   PL_check[OP_ENTERSUB]    = MEMBER_TO_FPTR(indirect_ck_entersub);
 316  }
 317 }